Alegrete, Brazil

Federal University of Pampa
Alegrete, Brazil
Time filter
Source Type

Mello-Carpes P.B.,Federal University of Pampa | Izquierdo I.,Grande Rio University | Izquierdo I.,Instituto Nacional Of Neurociencia Translacional Innt
Neurobiology of Learning and Memory | Year: 2013

The Nucleus of the Solitary Tract (NTS) receives gustatory and visceral information from afferent fibers in the vagus and projects to the Nucleus Paragigantocellularis (PGi), among several other brain region. PGi sends excitatory fibers, mostly glutamatergic, to the Locus Coeruleus (LC). In turn, LC sends noradrenergic projections to many areas of the brain, including hippocampus (HIPP) and amygdala. Here we show that the NTS-PGi-LC-HIPP pathway is required for the memory consolidation of object recognition (OR). The inhibition of NTS, PGi or LC by microinfusion of the GABAA receptor agonist, muscimol, into each of these structures up to 3h after object recognition memory training impairs its consolidation as assessed in a retention test 24h later. The posttraining microinfusion of the β-blocker, timolol into CA1 mimics this effect. Intra-CA1 NA microinfusion does not alter retention per se, but reverses the disruptive effect of muscimol given into NTS, PGi or LC. This effect of NA is shared by a microinfusion of NMDA into LC. These results support the idea that the NTS-PGi-LC-CA1 pathway contributes to memory consolidation through a β-noradrenergic mechanism in CA1. © 2012 Elsevier Inc.

Longaretti D.,Federal University of Pampa
EAMTA 2012 - Proceedings of the Argentine School of Micro-Nanoelectronics, Technology and Applications 2012 | Year: 2012

The goal of this paper is to present a tool for automatic synthesis of analog basic integrated blocks using the genetic algorithm heuristic and an external electrical simulator. The methodology is based on the minimization of a cost function and a set of constraints in order to size individual transistors of a given circuit. The synthesis methodology is implemented in Matlab and use GAOT (Genetic Algorithm Optimization Toolbox) as heuristic and Synopsys Synopsys HSPICE® simulator for circuit simulation. As circuit design example, this paper shows the application of the methodology for the design of an OTA Miller in 0.18μm fabrication technology. Monte Carlo simulations are performed in order to analyze yield in the final solution and the importance of the design centering. © 2012 EDIUNS.

Farina M.,Federal University of Santa Catarina | Avila D.S.,Federal University of Pampa | Da Rocha J.B.T.,Federal University of Santa Maria | Aschner M.,Vanderbilt University
Neurochemistry International | Year: 2013

Essential metals are crucial for the maintenance of cell homeostasis. Among the 23 elements that have known physiological functions in humans, 12 are metals, including iron (Fe) and manganese (Mn). Nevertheless, excessive exposure to these metals may lead to pathological conditions, including neurodegeneration. Similarly, exposure to metals that do not have known biological functions, such as mercury (Hg), also present great health concerns. This review focuses on the neurodegenerative mechanisms and effects of Fe, Mn and Hg. Oxidative stress (OS), particularly in mitochondria, is a common feature of Fe, Mn and Hg toxicity. However, the primary molecular targets triggering OS are distinct. Free cationic iron is a potent pro-oxidant and can initiate a set of reactions that form extremely reactive products, such as Oh. Mn can oxidize dopamine (DA), generating reactive species and also affect mitochondrial function, leading to accumulation of metabolites and culminating with OS. Cationic Hg forms have strong affinity for nucleophiles, such as -SH and -SeH. Therefore, they target critical thiol- and selenol-molecules with antioxidant properties. Finally, we address the main sources of exposure to these metals, their transport mechanisms into the brain, and therapeutic modalities to mitigate their neurotoxic effects. © 2012 Elsevier Ltd. All rights reserved.

Foletto M.C.,Federal University of Pampa | Haas S.E.,Federal University of Pampa
Anais Brasileiros de Dermatologia | Year: 2014

Cutaneous melanoma is a challenge to treat. Over the last 30 years, no drug or combination of drugs demonstrated significant impact to improve patient survival. From 1995 to 2000, the use of cytokines such as interferon and interleukin become treatment options. In 2011, new drugs were approved by the U.S. Food and Drug Administration, including peginterferon alfa-2b for patients with stage III disease, vemurafenib for patients with metastatic melanoma with the BRAF V600E mutation, and ipilimumab, a monoclonal antibody directed to the CTLA-4 T lymphocyte receptor, to combat metastatic melanoma in patients who do not have the BRAF V600E mutation. Both ipilimumab and vemurafenib showed results in terms of overall survival. Other trials with inhibitors of other genes, such as the KIT gene and MEK, are underway in the search for new discoveries. The discovery of new treatments for advanced or metastatic disease aims to relieve symptoms and improve patient quality of life. © 2014 by Anais Brasileiros de Dermatologia.

Dias-Da-Silva S.,Federal University of Pampa | Marsicano C.,Laboratorio Of Paleontologia Of Vertebrados
Journal of Systematic Palaeontology | Year: 2011

All stereospondyl taxa previously placed within Rhytidosteidae are reviewed in a phylogenetic context. A parsimony analysis shows that Pneumatostega, Trucheosaurus, Rhytidosteus and Nanolania are placed outside Rhytidosteidae. If an implied weighting method is introduced in order to downweight homoplastic characters, then these taxa are placed within rhytidosteids (with the exception of Rhytidosteus), thus forming a resolved monophyletic group. This group is supported by four synapomorphies, including a twisted pterygoid quadrate ramus and sculpture consisting of a reticulate pattern with pustules or nodules at the junction between adjacent crests and ridges. Based on the topology of a majority rule consensus tree, we postulate a close relationship among all eastern Gondwanan rhytidosteids (Australian and Indian taxa) and among western Gondwanan taxa (South America, South Africa and Madagascar). Laurasian Boreopelta and Peltostega are successive paraphyletic taxa of both eastern and western groups. The Australian family 'Derwentiidae' is nested within Rhytidosteidae and is redefined as a subfamily (Derwentiinae nov.) which also includes Indobrachyops. Peltosteginae and Indobrachyopidae as currently defined in the literature are not supported. Rhytidosteinae is also not supported because Laidleria, Pneumatostega and Rhytidosteus do not emerge as a clade. The presence of the rhytidosteid Trucheosaurus major in the Late Permian of Australia suggests that rhytidosteids were already diversified at that time. Increasing efforts to collect Upper Permian and Lower Triassic rhytidosteids should help to improve stratigraphical, palaeogeographical and phylogenetic information regarding this widespread group of temnospondyls. Copyright © 2011 The Natural History Museum.

Grigoletto F.B.,Federal University of Pampa | Pinheiro H.,Federal University of Santa Maria
IEEE Transactions on Industrial Electronics | Year: 2014

This paper presents a new flexible arrangement of static converters for grid-connected wind energy conversion systems (WECS). The proposed arrangement uses three-phase voltage-fed back-to-back mass-produced power converter modules with reconfiguration switches. The main features of the proposed flexible arrangement are as follows: 1) expanded reactive power capability limits; 2) high efficiency, mainly under low wind conditions where the active power is reduced; and 3) low current harmonic content. In addition, a detailed description of the operating modes, as well as of the grid, generator, and circulating current controller design, are given. Finally, experimental results support the theoretical development, and demonstrate the good performance and flexibility of the proposed arrangement. © 1982-2012 IEEE.

de David A.C.,University of Brasilia | Carpes F.P.,Federal University of Pampa | Stefanyshyn D.,University of Calgary
Journal of Sports Sciences | Year: 2015

Joint moments can be used as an indicator of joint loading and have potential application for sports performance and injury prevention. The effects of changing walking and running speeds on joint moments for the different planes of motion still are debatable. Here, we compared knee and ankle moments during walking and running at different speeds. Data were collected from 11 recreational male runners to determine knee and ankle joint moments during different conditions. Conditions include walking at a comfortable speed (self-selected pacing), fast walking (fastest speed possible), slow running (speed corresponding to 30% slower than running) and running (at 4 m · s−1 ± 10%). A different joint moment pattern was observed between walking and running. We observed a general increase in joint load for sagittal and frontal planes as speed increased, while the effects of speed were not clear in the transverse plane moments. Although differences tend to be more pronounced when gait changed from walking to running, the peak moments, in general, increased when speed increased from comfortable walking to fast walking and from slow running to running mainly in the sagittal and frontal planes. Knee flexion moment was higher in walking than in running due to larger knee extension. Results suggest caution when recommending walking over running in an attempt to reduce knee joint loading. The different effects of speed increments during walking and running should be considered with regard to the prevention of injuries and for rehabilitation purposes. © 2014, © 2014 Taylor & Francis.

Massing J.R.,Federal University of Santa Maria | Stefanello M.,Federal University of Pampa | Grundling H.A.,Federal University of Santa Maria | Pinheiro H.,Federal University of Santa Maria
IEEE Transactions on Industrial Electronics | Year: 2012

This paper presents a discrete-time adaptive current controller for grid-connected pulse width modulation voltage source converters with LCL filter. The main attribute of the proposed current controller is that, in steady state, the damping of the LCL resonance does not depend on the grid characteristic since the adaptive feedback gains ensure a predefined behavior for the closed-loop current control. An overview of model reference adaptive state feedback theory is presented aiming to give the reader the required background for the adaptive current control design. The digital implementation delay is included in the model, and the stability concerning the variation of the grid parameters is analyzed in detail. Furthermore, current distortions due to the grid background voltage are rejected without using the conventional stationary resonant controllers or the synchronous proportional-plus-integral controllers. Simulation and experimental results are presented to validate the analysis and to demonstrate the good performance of the proposed controller for grid-connected converters subjected to large grid impedance variation and grid voltage disturbances. © 2011 IEEE.

Pappas E.,Long Island University | Carpes F.P.,Federal University of Pampa
Journal of Science and Medicine in Sport | Year: 2012

Objectives: Higher side-to-side asymmetry among female athletes compared to their male counterparts during bilateral athletic tasks such as landing from a jump has been proposed as a potential source of non contact knee injuries. However, the kinematic symmetry and potential sex differences during the initial (and most dangerous) phase of bilateral landings have not been examined. The objective of this project is to evaluate lower extremity kinematic asymmetry among recreational athletes during forward jump landing and drop landing tasks. Design: Repeated measures laboratory experiment. Methods: Thirteen male and 15 female athletes performed landing tasks on a force plate while kinematic data were collected. Kinematic asymmetry between legs was calculated for the initial phase of landing for lower extremity kinematics. ANOVA tests and effect size calculations were used to measure the effect of sex, landing task and their interaction on kinematic asymmetry. Results: Athletes exhibited higher asymmetry for knee valgus (d=0.5, p=0.006) and hip adduction (d=0.5, p=0.057) when performing forward compared to drop landings. Females landed with greater knee valgus asymmetry than males during forward landings (d=0.7, p=0.078) and with greater ankle abduction asymmetry during drop landings (d=0.5, 0.091). Conclusions: Female athletes exhibited greater frontal plane knee and ankle kinematic asymmetry than males during forward landings which may be related to the higher rate of ACL injury. Forward landings elicited greater hip adduction and knee valgus asymmetries than drop landings and, therefore it may be more appropriate for field testing when screening for asymmetries. © 2011 Sports Medicine Australia.

The Rio do Rasto Formation (Permian of Southern Brazil) was previously regarded as Guadalupian-early Lopingian age. Three tetrapod-based localities are known: the Serra do Cadeado area, Aceguá and Posto Queimado. The latest tetrapod-based biostratigraphic contribution considers that the Posto Queimado and Aceguá faunas are coeval and Wordian (middle Guadalupian) in age, correlated to the Isheevo faunas from Eastern Europe and to the Tapinocephalus Assemblage Zone of South Africa; whereas the Serra do Cadeado fauna is Capitanian (late Guadalupian), correlated to the Kotelnich fauna of Eastern Europe and, from bottom to top, to upper Pristerognathus, Tropidostoma and lower Cistecephalus assemblage zones of South Africa. A re-evaluation of the tetrapods from the Rio do Rasto Formation and new fossil discoveries in the localities of Posto Queimado and Serra do Cadeado area (melosaurine and platyoposaurine temnospondyls, a basal anomodont, a dinocephalian and a basal dicynodont) supports a new tetrapod-based biostratigraphic scheme for the Rio do Rasto Formation. Accordingly, the age of the fauna at Aceguá is late Roadian-early Wordian, whereas the locality of Posto Queimado is late Wordian-Capitanian. The Serra do Cadeado Area is correlated with both southernmost ones (Guadalupian) but also Wuchiapinghian (early Lopingian). □Paraná Basin, Passa Dois Group, tetrapod biostratigraphy, Western Gondwana. © 2011 The Author, Lethaia © 2011 The Lethaia Foundation.

Loading Federal University of Pampa collaborators
Loading Federal University of Pampa collaborators